Sandblast apparatus



y 12, 1964 P. H. WILLIAMS 3,132,449

SANDBLAST APPARATUS Filed May 21, 1963 3 Sheets-Sheet 1 Fig.

Philip H Williams INVENTOR.

BY w

y 12, 4 P. H. WILLIAMS 3,132,449

SANDBLAST APPARATUS Filed May 21, 1963 3 Sheets-Sheet 5 Philip H.Williams IN VEN TOR now W 15M United States Patent Ofitice 3,132,449Patented May 12, 196% 3,132,449 SANDBLAST APPARATUS Philip H. Williams,San Jose, Calif., assighor to Victor C. Arispe, Sequel, Calif. Filed May21, 1963, Ser. No. 281,899 9 Claims. (CL 51-43) This invention comprisesa novel and useful sandblast apparatus and more particularly pertains toan apparatus of the same general type but constitutes an improvementover the sandblast apparatus disclosed in the prior patent of Victor C.Arispe, Patent No. 2,565,341, issued August 21, 1951.

There are conventional known types of sandblasting equipment in whichthe castings or work to be sandblasted are placed in a cylindricalbarrel or drum and tumbled about therein during rotation of the drumabout a central horizontal axis. In such equipment, a sandblast nozzlepositioned inside the rotating drum and directs its spray upon the workor articles tumbling about within the drum, and in order to seek a moreuniform treatment of the work by the blast, the sandblast nozzle isgiven an oscillatmg movement in order to cause the sandblast to travelalong the length of the drum and the work therein. It is withapparatuses of this type that the present inventron is particularlyconcerned and presents improvements and advantages asto structure andoperation thereover.

The chief difficulty encountered in sandblast apparatuses of the abovementioned type is the lack of uniformity or evenness in the sandblastingtreatment of the workpieces and the lack of uniformity of the pattern ofthe sandblasting upon the workpiecesi Usually, these disadvantages arisefrom lack of uniformity in the time during which the sandblast isapplied to different portions of the workpieces duringthe oscillatorypath of travel of the sandblast nozzle. A further difficulty rises froma lack of the ability .to precisely adjust and regulate the angle or"the sandblast throughout a wide range with respect to differentworkpieces in order to obtain a uniform treating etfect thereon. As aresult of these dithculties encounteredin prior apparatuses, thereresults a sandblasting operation which is not uniform as toits treatmentof the entire surface of the workpieces, requires an excessive amount oftime to complete the blasting operation and results in excessive coststherefor. i

It is therefore the primary purpose of this invention to provideiasandblast apparatus which will effectively overcome the above mentionedand other disadvantages oi prior sandblast equipment.

Basically, the essence of this invention resides in the provision of anapparatus in which the sandblast jet can be easily and quickly movedinto or out of the rotating work housing or shell together Withanimproved means for precisely and with celerity adjusting the positionofthe sandblast jet Wllhfe SpBCt tO the workpieces within the housingthroughout a Wide range of adjustment in order to obtain -the optimumWork-ing positionot the sandblast jet with respect tothe given workpieceor workpiecesfwithinthework hou 'ng.

More specifically, ove 5nd advantageousofeatures of this inventionreside in:

plate whereby to effect with celerity and certainty the adjustablepositioning of the jet nozzle throughout a wide range of positionswithin the work housing to thereby obtain a wide selection of patternsof abrasion by the sandblast jet. 7

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is a top plan view of one suitable embodiment of the sandblastapparatus incorporating therein the principles of this invention;

FIGURE 2 is a side elevational view, upon an enlarged scale, of theapparatus of FIGURE 1;

FIGURE 3 is an end elevational view taken on the left end of FIGURE 2with parts being broken away;

FIGURE 4 is a vertical central sectional view taken upon an enlargedscale and substantially upon the plane indicated by the section line d-4of FIGURE 1 and with parts being broken away;

FIGURE 5 is a vertical transverse sectional view taken substantiallyupon the plane indicated by the broken section line 5-5 of FIGURE 4;

FIGURE 6 is a detail view in horizontal section and upon an enlargedscale, being taken substantially upon the plane indicated by the sectionline 6-6 of FIGURE 4 and showing in particular the mounting andoscillating means for the jet nozzle in the jet housing; and

FIGURE 7 is a further detail view in vertical section being taken uponan enlarged scale substantially upon the plane indicated by the sectionline 77 of FIGURE 4 and shows certain details of the adjusting andmounting mechanism of the jet housing upon the adjustable stationarywork housing closure plate of the device. I

In the accompanying drawings there is disclosed by way of example onlyone preferred embodiment of an apparatus for carrying out the principlesof this invention including its novel method of operation. Theapparatus, indicated generally by the numeral 10 consists of a suitablesupport structure which includes a supporting .rail 1); which isassociated with astationary outer casing or housing lid whichconstitutes an enclosure of the sanoblast apparatus during its sandingoperation. Referring especially to FIGURE 4 it will be observed that thesupport means 12 comprises ahorizontally extending overhead rail whichmay be of I-beam configuration as shown and which extends into thestationary outer casing or housing 14. Supported upon this beam formovement longitudinallytherealong is a sandblasting element indicatedgen support rail extending into the outer casing 1d at the lower portionthereof with the apparatus in being mounted upon and projecting upwardlyabove the support rail. "In any event, it is essential for the purposesof this invention that the apparatus it shall be capable of movementlongitudinally upon its support means 12 so that it may be moved intoand out of the stationary outer casing 1 i With continuing reference toFIGURES 4 and 5 it will be observed that the, apparatus I6 includes acarriage which is'rnounted by upstandingbrackets 2t? and roller 22 upontherail 12 for movement therealong. Inasmuch as the structural detailsof the carriage in itself may be varied widely within the principles ofthis invention and in themselves form no part of the invention set forth4 and claimed hereinafter, and will be readily understood 3 by thoseskilled in the art, a further description and showing thereof is deemedto be unnecessary.

The outer housing 14 is provided with what may be termed its inner endwith a-stationary end wall 24 while its other end has an end wall 26provided with a relatively large opening 28 therein for a purpose to besubsequently set forth. Received in the lower end of the outer casingbetween the Walls 24 and 26 is a sand collecting device which may be inthe form of a bin or container 30 open at its top and into which thesand of the sandblasting operation as set forth hereinafter drops and iscollected, suitable conduit means as at 32 being provided for effectinga continuous withdrawal of the accumulating sand for reuse by thesandblast nozzle as set forth hereinafter.

Suspended from the carriage 18 as by means of a single bracket orsupport arm 34 is an axle 36 journaled in a bearing sleeve 38 of the arm34 and which axle is rigidly secured to and constitutes a support forthe closing end wall 40 of a rotatable cylindrical work housing ortumbling barrel 42 which is open at its right end as viewed in FIGURE 4.It will thus be observed that the barrel is supported cantilever fashionfrom the bearing sleeve 38 and the support arm 34 by the axle 36. Aplurality of apertures 44 which are preferably evenly and uniformlydistributed over the entire cylindrical circumference of tumbling barrelor drum 42 are provided for allowing the escape of the sand and air fromthe interior of the turnbling barrel.

The tumbling barrel has a horizontal axis which is the axis of the shaft36, about which the tumbling barrel rotates.

In order to effect this rotation there is preferably provided a sourceof power such as an electric motor 46 mounted upon the support carriage18 and which drives by means of a pulley 48 and a belt 50 a drivenpulley 52 secured to the outer end of the axle 36.

Air which conveys and discharges the sand of the sandblast mechanism ispermitted to escape from the interior of the stationary outer casing 14as by means of a sand discharge or outlet pipe 54.

In order to further support and guidably mount the open or right end ofthe tumbling barrel or drum 42, there is provided journaling meanstherefor such as a stationary support member or plate 56 carrieddependingly by the support carriage 18 and which has a plurality ofrollers 58 rotatably journaled upon a peripheral flange 60 of the member56.

These rollers engage against an annular track 62 secured to theperiphery of the drum 42.

A further stationary bearing support plate 64 is carried by the supportstructure 18 and has journaled thereon a series of rollers 66 whichengage and rotatably support the exterior surface of the drum. It willthus be apparent that the drum is rotatably journaled for rotation aboutits longitudinal axis while being dependingly secured to the supportcarriage 18 for movement therewith along the track 12 into and out ofthe outer casing 14.

A very important feature of this invention resides in the relativeproportions of the tumbling barrel. Ordinarily, tumbling barrels arerelatively long compared to their diameter. However, it is an importantfeature of this invention that the tumbling barrel is of relativelygreater diameter than its length so as to reduce the axial extent of thebarrel and of the stationary outer, casing 14. As a result of theseproportions, there is obviously relatively less travel required of anoscillating spray nozzle longitudinally of the barrel in order toproject the sandblast uniformly over the entire surfaces of the variousarticles received in the tumbling barrel.

With continuing reference to FIGURE 4 it will be noted that the end wall24 is provided with a central opening 68 therethrough through which isreceived a generally cylindrical sleeve 70 projecting inwardly of theouter casing 14.

Adjustably secured to the end Wall 24 is a mounting assembly indicatedgenerally by the numeral 74, to be hereinafter described, and by meansof which there is supported a horizontally extending jet housing 76which is preferably of cylindrical configuration and projects into theinterior of the tumbling barrel for a considerable distance therein. Aswill be best observed from a consideration of FIGURE 4 in conjunctionwith FIGURE 6, the housing 76 has end closures 78 and 80 at its oppositeends and is provided with a longitudinally extending slot or opening $1in one side thereof. Mounted within this housing and positioned thereinfor discharging the sandblast through the opening 81 with variouscontrolled paths of movement is a jet nozzle assembly indicatedgenerally by the numeral 82. This assembly includes a jet nozzle 84 ofany known and conventional type which in itself forms no part of thepresent invention, and which has a discharge nozzle 86 directed throughthe slot 81 for discharging the sandblast upon the objects within theinterior of the tumbling barrel. The jet nozzle 84 is supplied withcompressed air as through a flexible conduit 87 and with sand as throughthe flexible conduit 83, each of these conduits extending through theend Wall St and being connected to a suitable source of compressed air,not shown, and a suitable source of sand such as the hopper 90 mountedupon any suitable support means such as a bracket 92. It Will beunderstood that the sand conduits 32 previously mentioned and extendinginto the receptacle 30 remove sand therefrom and discharge it by anysuitable means, not shown, and as by a conduit 94 into the interior ofthe sand tank 90 from which the conveying air may escape therefrom as bya conduit 94.

Means are provided for effecting various controlled movements in acyclic manner to the nozzle assembly in order to vary the direction ofits sandblast. For this purpose, there is provided a supporting bracketassembly 96 which may be suitably carried by the end wall 24 and uponwhich is mounted a source of power such as electric motor 98 whichthrough the reduction gearing assembly 100 imparts rotation to acrankshaft 102 having a crank 104 thereon. As shown in greater detail inFIGURE 6, the crank is provided with a connecting rod 106 which ispivoted to the end of a reciprocating actuating shaft 108 journaled in apair of fixed bearings 110 and 112 provided upon the interior of thehousing 76. The jet nozzle 84 is itself fixedly secured to and carriedby a reciprocating supporting and driving shaft 114 which is journaledin the supporting bearings 116 and 118 likewise provided in the interiorof the housing 76. An arm 120 which is fixedly but adjustably securedupon the shaft 108 as by means of adjustable collars 122 is in turnfixedly secured to the shaft 114 whereby the latter will be reciprocatedin its bearings in response to reciprocation of the shaft 108. In thismanner, controlled reciprocation can be imparted to the nozzle 84 tocause the latter to travel in a rectilinear path in a direction which isparallel to the horizontal axis of the tumbling barrel in order that thespray from the nozzle may be uniformly directed along the length of thebarrel. It will be appreciated that any desired means can be providedfor varying the speed of this reciprocation, while the adjustableconnection of the arm 120 to the shaft 108 enables prev cise variationof the amplitude of reciprocation of the nozzle in the housing 76.

In order to effect rotational adjustment of the nozzle 84 and thus ofthe directionof the sandblast therefrom within the interior of thetumbling barrel 42, means are provided for rotating the entire jetassembly and its housing 76 about its axis and within its mounting means74. r

This mounting means, as shown best by reference to FIGURE 7, consists ofa base mounting plate which may be circular as shown at and which isrotatably journaled in and secured by a pair of arcuate retainingbrackets 132 against the face of the end wall 24 in a arsaaas manner tocompletely overlie and close the opening 68 in this end wall. The baseplate 13% is itself provided with a circular opening 134 therein andthis latter opening is also covered by an adjusting plate 136 which isrotatably retained upon the base plate 130 as by arcuate brackets 138.Finally, the cylindrical jet housing 76 is provided with an annularexternally projecting mounting flange 140 which completely overlies theopening 142 i in the plate 136 and which flange hill is rotatablyretained in arcuate retaining brackets 143 upon the plate 134.

It will be observed that various fastening means such as the bolts Md,1% and MS of the brackets 132, 138 and 143 respectively are employed toboth retain the respective supporting plates in position and to alsolock these plates in rotationally adjusted position. It will be observedthat the plate or flange 140 and the opening 141 which is covered bythis fiange are eccentrically disposed with respect to each of theplates 1% and 13%. Consequently, independent individual rotationaladjustment of any of these plates will produce a corresponding travel ofthe jet assembly housing 74: in a circular path of travel within theinterior of the tumbling barrel. As will be evident, various combinedmotions can be given to the jet housing 76 by corresponding jointadjustments of the various mounting plates. For exarnple, straight linetravel in a vertical or horizontal plane can be readily imparted to thejet housing and thus to the jet nozzle carried thereby. By means ofvarious manipulations of the mounting plates either singly or jointly avery wide variation both of the position of the nozzle within theinterior of the tumbling barrel and also the direction of the path ofthe sandblast from the nozzle is obtainable. This enables the nozzle tobe positioned at the most effective location for eliective sandblastingof the various articles placed in the tumbling barrel.

The method of operation performed by this invention is as follows. Withthe apparatus supported by its supporting carriage T3 at a positionoutside of the stationary outer casing lid, ready access can be had tothe open right end of the drum 42 for the introduction of or the removalof articles. With the drum loaded with articles to be sandblasted, thesupport carriage is then moved into the interior of the stationarycasing 14. it will be observed that during this operation the apparatuswill move through the opening 28 in the end Wall 26 which opening willthen be closed by the closure plate 29 which is fixedly carried by thesupport carriage 1th and will be moved into closing engagement with theopening 23 of the Wall 26. At the same time, during this movement, theopen right end of the tumbling barrel is moved towards the stationaryclosure carried by the wall 24 and the stationary jet housing assemblysupported thereby. This enables the jet housing assembly to beautomatically and readily removed from the interior of the tumblingbarrel each time the latter is withdrawn from the stationary casing 14,so that ready access can be had to the jet housing assembly forinspectionof or servicing of any of its components and for furtherrendering the full area of the open end of the tumbling barrel availablefor access to its interior.

With the apparatus in the position shown in FIGURE 4, and the tumblingbarrel now moved into the interior of the stationary casing 14, the openend of the drum will now be closed by the closure member carried by thestationary outer casing wall 24. Thus, the interior of the drum issealed except for the openings 44 which permit the escape of sand andair from theinterior of the drum during the operation of thesandblasting spray.

Continuous rotation of the drum by the power source carried by thesupport carriage 18 presents the articles therein in various attitudesfor treatment by the sandblast. Further, the latter by virtue of itscombined rectilinear reciprocation through the motor 98 and thecrankshaft 102 travels continuously throughout the major length of thedrum. At the same time, the angle of impingement of this spray upon thearticles of the drum can be precisely and widely varied in accordancewith the mounting means 74 as previously described.

As emphasized hereinbefore, the drum is of relatively large diameter ascompared to its length. This important feature of the invention producesa number of advantages as follows:

(1) The enlarged diameter, in contrast with the more conventionalproportions of tumbling barrels, afifords suilicient room within thedrum for positioning the jet assembly, for readily adjusting it and forthe insertion or Withdrawal of the assembly as may be desired.

(2) It enables the jet assembly to be disposed perpendicularly of theface of the work, an arrangement im possible with the conventionalarrangement of a jet discharging through and into the open end of thedrum.

(3) The greater diameter and decreased length provide a drum capacityequal to that of a longer drum of con ventional proportions but insuresthat the abrasive spray Will cover and treat more effectively andefhciently a greater amount of material in a unit of time. As a resultof the uniformly greater concentration or" the spray over the length ofthe Work there are less dead spots or thinly sprayed areas upon thework, effecting a higher efficiency of operation, increased productionand lower costs.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

1. A sandblast apparatus comprising a support structure, a work housingconsisting of a drum having an open end and a central horizontal axis,means mounting said housing for rotation about said axis, means forrotating said housing about said axis, a closure for the open end ofsaid housing and mounted upon said support structure, means effectingrelative movement of said housing toward and from said closure wherebythe latter will selectively close and uncover said open end, ahorizontally extending jet housing carried by and extending through saidclosure for relative movement of said jet housing in a direction axiallyof said Work housing, a sandblast jet mounted in said jet housing andhaving a jet nozzle positioned to discharge a sand spray transversely ofsaid work housing, means supplying sand and air under pressure to saidjet nozzle, means for adjusting said jet within said work housingselectively, both vertically and horizontally While maintaining thecentral horizontal axis of said jet housing in parallel position.

2. The combination of claim 1 wherein said work housing has a closedother end, an axle securedto said closed end to said work housingmounting means including a journal receiving and supporting said axle,said Work housing rotating means being connected to said axle forrotating the latter.

3. The combination of claim 2 wherein said drum consists of a perforatedcylinder and is of greater diameter than length.

4. The combination of claim 1 wherein said suppor structure includes astationary casing, said closure comprising a stationary member carriedbysaid stationary casing and operable to respectively uncover and closesaid open end upon movement of said drum away from and towards saidclosure.

5. The combination of claim 1 wherein said jet housing has-a slot in oneside thereof, said jet nozzle being positioned for discharging a blastof sand through said slot and against the surface of articles in saiddrum, means for reciprocating said jet nozzle horizontally and axiallyin said jet housing.

6. The combination of claim 1 wherein said jet housing adjusting meanscomprises a series of mounting plates disposed in flat, side by sideengagement and rotatably journaled upon each other for relative rotationand having registered openings through which said jet housing projectsinto the interior of said work housing, means for rotatably journalingone of said mounting plates upon said closure, said jet housing beingcarried by another of said mounting plates and being disposedeccentrically of the remainder of said mounting plates.

7. A sandblast apparatus comprising a tumbling barrel rotatable about ahorizontal axis and having an open end, a stationary housing forenclosing said barrel and having a closure for said open end, a trackextending into said stationary housing, support means movably mountedupon said track for movement into and out of said stationary housing androtatably journaling said barrel, a sandblast jet assembly including ajet nozzle carried by said closure for projection into said barrelthrough said open end, means carried by said support means for effectingrotation of said barrel, means carried by said closure for efiectingreciprocation of said jet nozzle in said barrel.

8. The combination of claim 7 including means mounting said jet assemblyupon said closure for selective adjustment in both vertical andhorizontal directions relative to the aXis of said barrel.

9. The combination of claim 8 wherein said adjusting means enablesmovement of said jet assembly for straight line motion.

References Cited in the file of this patent UNITED STATES PATENTS1,476,619 Kemp Dec. 4, 1923 1,710,166 Hull Apr. 23, 1929 1,948,873Vessey Feb. 27, 1934 2,565,341 Arispe Aug. 21, 1951

7. A SANBLAST APPARATUS COMPRISING A TUMBLING BARREL ROTATABLE ABOUT AHORIZONTAL AXIS AND HAVING AN OPEN END, A STATIONARY HOUSING FORENCLOSING SAID BARREL AND HAVING A CLOSURE FOR SAID OPEN END, A TRACKEXTENDING INTO SAID STATIONARY HOUSING, SUPPORT MEANS MOVABLY MOUNTEDUPON SAID TRACK FOR MOVEMENT INTO AND OUT OF SAID STATIONARY HOUSING ANDROTATABLY JOURNALING SAID BARREL, A SANDBLAST